Description
Phenylmethylsulfonyl fluoride (PMSF) is a fast-acting, irreversible serine protease inhibitor. By covalently modifying the active-site serine residue, PMSF protects proteins from proteolytic degradation during cell lysis, purification, and assay workflows. Its inclusion in protease inhibitor cocktails offers broad-spectrum protection in proteomics, structural biology, and enzymology studies. PMSF is also used in crystallography to label catalytic serines, providing insights into enzyme mechanism and structure.
GoldBio’s high-purity PMSF delivers reliable performance in critical experiments, with rapid inhibition kinetics and proven effectiveness at 0.1–1mM concentrations. Stored as a stable crystalline powder and easily prepared in organic solvents, PMSF is an essential reagent for preserving protein integrity and ensuring reproducible research outcomes.
Note: To enable us to avoid hazardous shipping fees, U.S. domestic ground shipments of PMSF will be shipped as a limited quantity exception for the 25 g, 50 g, and 100 g pack sizes. In some instances, GoldBio may ship 50 g as 2 x 25 g or 100 g as 4 x 25 g to qualify for a small quantity exception.
PMSF is inactivated in aqueous solutions. The rate of inactivation increases with increasing pH and is faster at 25°C than at 4°C. The half-life of a 20mM aqueous solution of PMSF is ~35 minutes at pH 8.0. This short half-life means that aqueous solutions of PMSF can be safely discarded after they have been rendered alkaline (pH >8.6) and stored for several hours at room temperature.
Common Research Applications
(Click each for more information)
Inhibition of Serine Proteases During Cell Lysate Preparation
-
Purpose: To prevent proteolytic degradation of proteins immediately after cell or tissue disruption, ensuring accurate downstream analysis.
-
How It Works: PMSF irreversibly inhibits serine proteases such as trypsin, chymotrypsin, and thrombin by covalently reacting with the active-site serine residue, blocking catalytic activity.
-
Applications: Standard additive to lysis buffers in biochemistry and molecular biology for maintaining protein integrity in crude extracts.
James, G. T. (1978). Inactivation of the protease inhibitor phenylmethylsulfonyl fluoride in buffers. Analytical Biochemistry, 86(2), 574–579.
Use in Protease Inhibitor Cocktails for Protein Purification and Analysis
-
Purpose: To provide broad-spectrum protection against proteolysis during protein purification workflows by combining PMSF with inhibitors targeting other protease classes.
-
How It Works: PMSF contributes irreversible serine protease inhibition within multi-target cocktails, complementing inhibitors for cysteine proteases, metalloproteases, and aspartic proteases.
-
Applications: Proteomics, biochemical purification, mass spectrometry sample preparation, and affinity chromatography.
Andrés-Colás, N., & Van Der Straeten, D. (2017). Optimization of non-denaturing protein extraction conditions for plant PPR proteins. PLOS ONE, 12(11), e0187753.
Preservation of Protein Stability During Downstream Purification and Analysis
-
Purpose: To maintain protein structure and function during multi-step purification processes after cell lysis.
-
How It Works: PMSF inhibits proteases remaining in the sample, preventing degradation during chromatography, electrophoresis, and ultracentrifugation.
-
Applications: Native protein purification, functional studies, and structural analysis.
Kushnirov, V. V. (2000). Rapid and reliable protein extraction from yeast. Yeast, 16(9), 857–860.
Covalent Labeling of Active-Site Serines for Mechanistic and Structural Studies
-
Purpose: To identify and characterize catalytic serine residues in enzymes for mechanistic enzymology and structural biology.
-
How It Works: PMSF forms a stable sulfonylated adduct with the active-site serine, which can be visualized through X-ray crystallography or confirmed by mutagenesis.
-
Applications: Catalytic residue identification, enzyme mechanism studies, and structural accessibility analysis of enzyme active sites.
Das, A. K., Bellizzi, J. J., Tandel, S., Biehl, E., Clardy, J., & Hofmann, S. L. (2000). Structural basis for the insensitivity of a serine enzyme (palmitoyl-protein thioesterase) to phenylmethylsulfonyl fluoride. Journal of Biological Chemistry, 275(31), 23847–23851.
Short-Term Stabilization of Enzyme Activity in Biochemical Assays
-
Purpose: To maintain enzyme activity during biochemical assays by preventing proteolytic degradation of target proteins.
-
How It Works: PMSF rapidly and irreversibly inhibits contaminating serine proteases in crude or partially purified samples, preserving the target enzyme’s functional state.
-
Applications: Enzyme kinetics, binding assays, and short-term biochemical measurements requiring reproducible results.
Adinarayana, K., Ellaiah, P., & Prasad, D. (2003). Purification, characterization and optimization of serine protease from Bacillus subtilis P13. Process Biochemistry, 38(7), 909–915.
Benefits:
Prevents Proteolytic Degradation – Protects proteins from serine protease activity during cell lysis and purification. Enhances Data Reliability – Maintains protein structure and function for accurate analytical results. Versatile Workflow Integration – Functions as a standalone inhibitor or as part of multi-target protease inhibitor cocktails. Supports Structural Biology – Covalently labels active-site serines for mechanistic and crystallographic studies. Rapid Action – Irreversibly inactivates proteases within minutes, minimizing handling time.
Storage/Handling:
Store desiccated at 4°C.
Soluble in DMSO or 100% Ethanol.
Protect from light. Hygroscopic.
Powered by Bioz
